Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income	$ 582	$ 321
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	498	500
Deferred income tax expense (benefit)	2	(4)
Changes in current assets and current liabilities	(1,026)	151
Changes in deferred charges and credits and other operating activities, net	82	20
Net cash provided by operating activities	138	988
Cash flows from investing activities:
Capital expenditures	(356)	(279)
Deferred turnaround and catalyst costs	(220)	(245)
Investments in joint ventures	(55)	(117)
Acquisition of undivided interests	(85)	(72)
Capital expenditures of certain variable interest entities	(28)	0
Other investing activities, net	(8)	(1)
Net cash used in investing activities	(752)	(714)
Cash flows from financing activities:
Proceeds from issuance of Valero Energy Partners LP debt	498	0
Repayments of debt and capital lease obligations	(415)	(5)
Purchase of common stock for treasury	(320)	(314)
Common stock dividends	(345)	(315)
Proceeds from issuance of Valero Energy Partners LP common units	0	35
Contribution from noncontrolling interest	32	0
Distributions to noncontrolling interests	(11)	(34)
Other financing activities, net	(12)	(19)
Net cash used in financing activities	(573)	(652)
Effect of foreign exchange rate changes on cash	(5)	25
Net decrease in cash and temporary cash investments	(1,192)	(353)
Cash and temporary cash investments at beginning of period	5,850	4,816
Cash and temporary cash investments at end of period	$ 4,658	$ 4,463